The objectives of the contract are: (1) To determine prevalence rates of alcoholism in ten demographically sampled American Indian tribes using psychiatric interviews to rigorously diagnose alcoholism; (2) To systematically diagnose conditions which are often comorbid with alcoholism including drug abuse, depression, and antisocial personality; (3) To address crucial antecedents and consequences of alcoholism and environmental issues in alcohol vulnerability such as posttraumatic stress, violence, acculturation, and child abuse; and, (4) To investigate genetic vulnerability factors for tribal populations with high and low rates of alcoholism. A blood sample for genetic analyses will be collected from each individual who is interviewed in this study.